The present invention pertains to a device for moving a book, a bound book block or a book block that is loosely gathered of sheets and/or folded sections or similar printed book products.
Devices of the aforementioned type, in which the printed book product is fixed between clamping jaws, are used for feeding the printed product to a processing station or for transferring the printed product from this processing station to the next processing station or for delivering the printed product from the processing station, without the individual components of the printed product such as, e.g., the sheets and/or folded sections of an unbound book block shifting relative to one another such that they are no longer mutually aligned. A gripped delivery is also beneficial with respect to the quality of a freshly bound printed product such as, e.g., a freshly cased-in and/or joint-formed book.
EP 790 139 B1 describes a feeding device for a perfect-binding machine with a gripper that can be pivoted back and forward about a pivoting axis in order to transfer an unbound book block from a horizontal transfer position into an upright position above a block clamp of the perfect-binding machine that subsequently receives the book block. The gripper is opened and closed by means of a cogwheel mechanism that is driven in a rotative fashion by a drive that is arranged on the gripper and makes it possible to displace the assigned clamping jaw parallel to the other stationary clamping jaw.
DE 10 2004 006 128 A1 shows and describes a turning device, by means of which books received in an upright position are taken hold of, pivoted outward transverse to the feed transport direction and transferred into a defined horizontal delivery position that is spaced apart from the feed transport path in a synchronized fashion. The turning device comprises four grippers that jointly revolve in an intermittent fashion, wherein the grippers successively receive the books and respectively deliver the books after three 90° turning steps in order to return into the receiving position with the fourth turning step. The grippers are designed in such a way that an inner clamping plate can be adjusted to the format thickness and an outer clamping plate can be actuated by a pneumatic cylinder in order to clamp the books.
The disadvantage of these known devices can be seen in that the driving means for realizing the opening and closing movements are also moved. This increases the weight to be moved and the connecting lines are continuously subjected to mechanical stress. In revolving devices as it is the case with DE 10 2004 006 128 A1, a complicated rotary leadthrough for the connecting lines is also required.
DE 102 46 077 A1 discloses a clamping device that can be turned by plus 90° or minus 90° about the center line of a sheet stack accommodated therein. The clamping jaws are opened and closed symmetrically referred to a central plane, wherein the clamping jaws are spring-mounted on pressure pads that can be adjusted into a closed position and an open position. For this purpose, coupling rods are used in order to eccentrically connect the pressure pads to worm gears that are connected to and driven by endless screws such that they can be turned back and forth by 180° between a coinciding state that is assigned to the closed position and an extended state of the coupling rod and the worm gear that is assigned to the open position. The endless screws can be actuated manually or in a motor-driven fashion, wherein the motor drive does not participate in the rotation of the clamping device. The closed position and the open position are also secured when the endless screws are not driven due to the self-locking worm gear pair and the aforementioned dead-center positions of the coupling rod and the worm gear.
The disadvantage of the clamping device known from DE 102 46 077 A1 can be seen in that the clamping force exerted upon the printed product by the clamping jaws cannot be variably adjusted. The clamping force specifically results from the deflection of the clamping jaw resting against the printed product relative to the pressure pad that is adjusted inward into a fixed position, wherein the clamping force increases proportionally with the product thickness. The opening and closing of the clamping device only takes place in its rotative end positions, in which the endless screws are connected to and driven by the motor drive, such that the width of the opening between the clamping jaws cannot be adjusted during the rotation of the clamping device.